The present invention relates to a new and distinct cultivar of Spiraea, a deciduous hardy ornamental shrub used for planting in the garden and landscape. The new variety is known botanically as Spiraea japonica and will be referred to hereinafter by the cultivar name ‘Walplum’.
‘Walplum’ is the result of a breeding and selection program involving several thousand plants, and carried out by the inventor between 1984 and 1990 at the inventor's nursery in West Sussex, United Kingdom. The objective of the breeding program was to develop compact and stable varieties of Spiraea japonica with colorful foliage.
Commencing in 1984, the inventor sowed seeds of self-pollinated plants of Spiraea japonica ‘Goldflame’ (unpatented). The most promising seedling selections were utilized for two subsequent cycles of self-pollination and selection. In 1990, the inventor raised approximately 1,000 seedlings of which the majority were green in color. The inventor observed that approximately ten seedlings exhibited compact forms, smaller leaves, colorful new shoot tips and attractive green foliage and bright flowers when mature. From these seedlings, ‘Walplum’ was chosen for increase and commercial introduction.
‘Walplum’ was first asexually propagated by the inventor at the inventor's nursery in West Sussex, United Kingdom in 2012 using softwood cuttings. Since that time, under careful observation, the distinguishing characteristics have been determined stable and uniform in successive generations.